1. Field of the Invention
The present invention relates to an original cover closer for use in a copying machine, a facsimile machine, a scanner or a multifunctional device thereof and the like.
2. Description of the Background Art
A conventional type of this original cover closer includes a mounting member which is mounted on the main body of a copying machine, a supporting member which is pivotally mounted on the mounting member and supporting an original cover, a first and a second slider which are slidably housed in the support member, a compression coil spring which is placed between these sliders and urged in the direction to open the original cover, and a fluid damper which is interposed between the attachment member and the support member and can operate only when the open angle of the support member is no smaller than a predetermined closing angle (for example, as described in Japanese Utility Model Registration Publication No. 2589714).
For example, in the case of the damper device disclosed in the Japanese Utility Model Registration Publication, the energy absorption capability of the damper is constant as illustrated in FIG. 4A, and thereby it is necessary to provide a damper having an appropriate energy absorption capability suitable for the weight of the original cover (ADF).
This requirement decreases the productivity while pushing up the cost.